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Always pass weak reference of self into block in ARC?
... be the cause of these blocks retaining self and keeping it from being dealloced ? The question is, should I always use a weak reference of self in a block ?
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mongodb: insert if not exists
... has built-in support for this. Pass an extra parameter to your update() call: {upsert:true}. For example:
key = {'key':'value'}
data = {'key2':'value2', 'key3':'value3'};
coll.update(key, data, upsert=True); #In python upsert must be passed as a keyword argument
This replaces your if-find-els...
Call one constructor from another
...will be executed first then it will get back to the string version? (Like calling super() in Java?)
– Rosdi Kasim
Dec 18 '13 at 16:49
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When are you supposed to use escape instead of encodeURI / encodeURIComponent?
... section B.2.1.2 escape and the introduction text of Annex B says:
... All of the language features and behaviours specified in this annex have one or more undesirable characteristics and in the absence of legacy usage would be removed from this specification. ...
... Programmers should not us...
Python None comparison: should I use “is” or ==?
...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects)
In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity:
lst = [1,2,3]
lst == lst[:] # This is Tr...
Run a Python script from another Python script, passing in arguments [duplicate]
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I believe it's generally preferable to use subprocess.Popen over os.system: docs.python.org/library/subprocess.html#replacing-os-system.
– Katriel
Sep 23 '10 at 20:15
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how to mysqldump remote db from local machine
... a database on a remote server, but the server does not have mysqldump installed. I would like to use the mysqldump on my machine to connect to the remote database and do the dump on my machine.
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Are there any disadvantages to always using nvarchar(MAX)?
In SQL Server 2005, are there any disadvantages to making all character fields nvarchar(MAX) rather than specifying a length explicitly, e.g. nvarchar(255)? (Apart from the obvious one that you aren't able to limit the field length at the database level)
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How to get object length [duplicate]
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This is actually worse than using a simple loop and counter because of the added overhead of the callback function.
– nullability
Feb 19 '13 at 17:35
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Rename MySQL database [duplicate]
...atabase with the database name you wanted.
The short, quick steps without all the above explanation are:
mysqldump -u root -p original_database > original_database.sql
mysql -u root -p -e "create database my_new_database"
mysql -u root -p my_new_database < original_database.sql
mysql -u roo...